【C#-題庫】函式與程序

出處：http://www.indiabix.com/c-sharp-programming/functions-and-subroutines/

底下程式輸出為何？

namespace IndiabixConsoleApplication
{ 
    class SampleProgram
    {
        static void Main(string[] args)
        { 
            int num = 1;
            funcv(num); 
            Console.Write(num + ", "); 
            funcr(ref num); 
            Console.Write(num + ", ");
        }
        static void funcv(int num)
        { 
            num = num + 10; Console.Write(num + ", ");
        }
        static void funcr (ref int num)
        { 
            num = num + 10; Console.Write(num + ", ");
        } 
    } 
}

A. 1, 1, 1, 1,
B. 11, 1, 11, 11,
C. 11, 11, 11, 11,
D. 11, 11, 21, 11,
E. 11, 11, 21, 21,